The present invention relates to razors, and particularly relates to a platform, handle and shield assemblage for a safety razor. More particularly, the present invention relates to novel and unique platform structure for centering the handle with respect to the platform and maintaining a tight fit therebetween, as well as a shield and platform construction for facilitating application of the shield to the platform.
Safety razors are commonly formed of a handle secured at one end to a platform, the platform in turn mounting a subassembly for carrying one or more razor blades and a cap member for retaining the blades in assembly. The razor is frequently provided with a shield to protect the user from injury resulting from inadvertent contact with the blade edge and to protect the blade edge from damage during shipping, handling, etc. The handle, platform, cap and shield are usually formed of plastic material.
In the manufacture and assembly of the various plastic parts forming disposable, relatively inexpensive safety razors, fundamental design criteria, oftentimes conflicting, must be met. For example, the connection between the handle and the platform must be secure, tight, and readily adaptable to automated processes. The parts must be capable of being molded with an economy of material without sacrificing the integrity of the design. Accurate placement of the handle vis-a-vis the platform must be facilitated. Similarly, the interconnection of the shield and the platform serving as a guard for the razor oftentimes lies off-center and it is difficult to accurately center the shield along the longitudinal extent of the platform. Hence, the shield frequently affords protection along only a portion of the length of the blade. Additionally, the shield is sometimes difficult to place on the platform without risk of injury from the blade, the same risk which the shield seeks to protect against.
According to the present invention, there is provided a novel and improved safety razor having various advantages in construction and assembly in comparison with the prior safety razors and which meets the above-noted design criteria. Particularly, the safety razor of the present invention provides a handle having a head with a pair of projections or tongues along one edge of the head. The tongues are received in undercut openings formed in a wall which projects from the underside of the razor platform. The edge of the platform opposite the wall receives the opposite edge of the handle head in a snap-fit relation. Thus, when the tongues are disposed in the undercut openings the handle may be pivoted to snap the opposite edge of the handle head past the edge of the platform to finally seat the handle head against the platform.
Features of the present invention include a pair of crush ribs which project from the underside of the platform adjacent the projecting wall for engagement along the upper surface of the handle head. As the head is pivoted into final position, it engages the crush ribs, which then serve as a fulcrum for further pivoting. When the handle head obtains final securement along the underside of the platform, the crush ribs bias the head and platform away from one another to maintain a tight fit between the handle edges on one hand and the edge of the platform and the undercuts along the platform on the other hand.
A further feature of the present invention provides for automatically centering the handle head relative to the platform when the handle and platform are pivoted relative to one another into final securement. When the tongues are received in the undercut openings in the platform, relative pivotal action between the handle and the platform locates the side edges of the handle head in engagement with a pair of centering ribs. These centering ribs have tapered surfaces which longitudinally shift the platform and handle head relative to one another in response to the pivoting action to center the platform and head.
A further feature of the present invention facilitates centering the shield with respect to the platform when it has been initially snapped onto the safety razor in an off-center position. To accomplish this, chamfers are formed along the inside end edges of the generally channel-shaped shield and also along the underside of the razor head. This enables the shield to cam upwardly against the raised end edges of the cap at either of the opposite ends of the blade head. This permits inward projections at each of the lower end corners of the shield to engage chamfered surfaces and stops along the lower corners of the platform, thus detenting the shield in a centered position. The shield is also formed symmetrically about its long axis. This facilitates orientation of the shield on the blade head during production, as well as by the consumer.
Accordingly, in one aspect of the present invention, there is provided a razor blade assemblage comprised of a razor blade handle having a head, the head having opposed edges, with one of the edges having a projection and an abutment. A platform is provided for carrying at least one razor blade on an upper side thereof, the platform having an opposite lower side. The platform also has a locking element projecting from its lower side adjacent an edge thereof for engaging the other edge of the head. A wall projects from the lower side of the platform spaced from the edge thereof and has means defining at least one opening therein for receiving the projection. The platform wall also includes a stop. The projection on the handle head is received in the wall opening with the head abutment engaging the platform stop. The platform locking element and the other edge of the head are cooperable to enable the latter edge to snap past the locking element into final locked position against the underside of the platform.
Preferably, means are carried by the platform for centering the head along the underside of the platform, as well as for biasing the head in a direction away from the platform. The centering means includes a pair of longitudinally spaced centering ribs projecting from the underside of the platform, each rib having a tapered edge for engaging the sides of the head or centering the latter when the head is applied to the platform. The biasing means includes a pair of crush ribs which serve as a fulcrum for pivoting the head and platform relative to one another to enable tight-fitting engagement between the head and handle in final assembly.
In another aspect of the present invention, a shield is provided for overlying the platform, the shield being generally co-extensive in length with the platform and generally channel-shaped in cross-section with open opposite ends. Each lower edge of the platform has a chamfered surface adjacent its opposite ends and each lower edge of the shield has a projection adjacent opposite ends thereof for engaging the chamfered surfaces of the platform for retaining the shield on the razor blade. Preferably, the end edges of the shield are tapered or chamfered to facilitate endwise centering of the shield on the platform.
Accordingly, it is a primary object of the present invention to provide a novel and improved safety razor construction and assembly having structure cooperating between the platform and handle for centering these two parts relative to one another upon their assembly and affording a tight assembly. Additionally, the shield and razor head are constructed to facilitate centering the shield on the head and detenting the shield in its centered position on the head.
These and further objects and advantages of the present invention will become more apparent upon reference to the following specification, appended drawings and claims.